The Streptococci make up a medically important genera of microbes known to cause several types of disease in humans, including, for example, otitis media, conjunctivitis, pneumonia, bacteremia, meningitis, sinusitis, pleural empyema and endocarditis, and most particularly meningitis, such as for example infection of cerebrospinal fluid. Since its isolation more than 100 years ago, Streptococcus pneumoniae has been one of the more intensively studied microbes. For example, much of our early understanding that DNA is, in fact, the genetic material was predicated on the work of Griffith and of Avery, Macleod and McCarty using this microbe. Despite the vast amount of research with S. pneumoniae, many questions concerning the virulence of this microbe remain. It is particularly preferred to employ Streptococcal genes and gene products as targets for the development of antibiotics.
The frequency of Streptococcus pneumoniae infections has risen dramatically in the past few decades. This has been attributed to the emergence of multiply antibiotic resistant strains and an increasing population of people with weakened immune systems. It is no longer uncommon to isolate Streptococcus pneumoniae strains which are resistant to some or all of the standard antibiotics. This phenomenon has created a demand for both new anti-microbial agents, vaccines, and diagnostic tests for this organism.
UMP kinase is involved in the biosynthesis of pyrimidine triphosphate nucleosides from glucose metabolism intermediates via the de novo pathway or from exogenous uracil and uridine. The pyrimidine triphosphate nucleotides are precursors in the biosynthesis of macromolecules such as RNA, DNA, phospholipids and peptidoglycan.
The essential nature of the gene product of pyrH in Escherichia coli has been demonstrated by the construction of temperature sensitive mutants (Yamanaka, K., Ogura, T., Niki, H., and Hiraga, S. 1992. J. Bacteriol. 174, 7517-7526). Cold sensitive mutants have also been isolated in Escherichia coli (Yamanaka, K., Ogura, T., Niki, H., and Hiraga, S. 1992. J. Bacteriol. 174, 7517-7526. Bucurenci, N., Serina, L., Zaharia, C., Landais, S., Danchin, A., and Barzu O. 1998. J. Bacteriol. 180, 473-477) and Salmonella typhimurium (Ingraham, J. L., and Neuhard, J. 1972. J. Biol. Chem. 247, 6259-6265). Furthermore, consistent with the important physiological role of UMP kinase, the pyrH mutants show pleiotrophic effects including inhibition of macromolecule synthesis, defects in the membrane and change in the cell morphology (Yamanaka, K., Ogura, T., Niki, H., and Hiraga, S. 1992. J. Bacteriol. 174, 7517-7526).
Clearly, there exists a need for factors, such as the pyrH embodiments of the invention, that have a present benefit of being useful to screen compounds for antibiotic activity. Such factors are also useful to determine their role in pathogenesis of infection, dysfunction and disease. There is also a need for identification and characterization of such factors and their antagonists and agonists to find ways to prevent, ameliorate or correct such infection, dysfunction and disease.
Certain of the polypeptides of the invention possess amino acid sequence homology to a known Bacillus subtilis smbA, Synechocystis sp. pyrH, Mycobacterium leprae pyrH, Mycobacterium tuberculosis pyrH, Escherichia coli smbA, Haemophilus influenzae pyrH, Helicobacter pylori pyrH, Mycoplasma pneumoniae pyrH, Chlamydia trachomatis pyrH, Mycoplasma genitalium smbA, Thermus aquaticus pyrH, Archaeoglobus fulgidus pyrH, Methanococcus jannaschii pyrH, Pyrococcus horikoshii pyrH and Borrelia burgdorferi smbA protein. See GeneBank Z99112; GeneBank D90915; GeneBank Z97369; GeneBank Z74024; GeneBank D26562 and X78809; GeneBank U32786; GeneBank AE000589; GeneBank AE000021; GeneBank U60196; GeneBank U39730; GeneBank X83598; GeneBank AE000962; GeneBank U67566; GeneBank AB005215; GeneBank AE001158.